11:26 a.m.: United Airlines reports that United Flight 93, en route from Newark, New Jersey, to San Francisco,
California, has crashed in Pennsylvania. The airline also says that it is "deeply concerned" about United Flight
175.

11:59 a.m.: United Airlines confirms that Flight 175, from Boston to Los Angeles, has crashed with 56 passengers
and nine crew members aboard. It hit the World Trade Center's south tower.

12:04 p.m.: Los Angeles International Airport, the destination of three of the crashed airplanes, is evacuated.

12:15 p.m: San Francisco International Airport is evacuated and shut down. The airport was the destination of
United Airlines Flight 93, which crashed in Pennsylvania.

12:15 p.m.: The Immigration and Naturalization Service says U.S. borders with Canada and Mexico are on the highest
state of alert, but no decision has been made about closing borders.

12:30 p.m.: The FAA says 50 flights are in U.S. airspace, but none are reporting any problems.

1:04 p.m.: Bush, speaking from Barksdale Air Force Base in Louisiana, says that all appropriate security measures
are being taken, including putting the U.S. military on high alert worldwide. He asks for prayers for those killed
or wounded in the attacks and says, "Make no mistake, the United States will hunt down and punish those responsible
for these cowardly acts."

1:27 p.m.: A state of emergency is declared by the city of Washington.

1:44 p.m.: The Pentagon says five warships and two aircraft carriers will leave the U.S. Naval Station in Norfolk,
Virginia, to protect the East Coast from further attack and to reduce the number of ships in port. The two carriers,
the USS George Washington and the USS John F. Kennedy, are headed for the New York coast. The other ships headed to
sea are frigates and guided missile destroyers capable of shooting down aircraft.

1:48 p.m.: Bush leaves Barksdale Air Force Base aboard Air Force One and flies to an Air Force base in Nebraska.

2 p.m.: Senior FBI sources tell CNN they are working on the assumption that the four airplanes that crashed were
hijacked as part of a terrorist attack.

2:30 p.m.: The FAA announces there will be no U.S. commercial air traffic until noon EDT Wednesday at the
earliest.

2:49 p.m.: At a news conference, Giuliani says that subway and bus service are partially restored in New York City.
Asked about the number of people killed, Giuliani says, "I don't think we want to speculate about that -- more than
any of us can bear."

3:55 p.m.: Karen Hughes, a White House counselor, says the president is at an undisclosed location, later revealed
to be Offutt Air Force Base in Nebraska, and is conducting a National Security Council meeting by phone. Vice
President Dick Cheney and National Security Adviser Condoleezza Rice are in a secure facility at the White House.
Defense Secretary Donald Rumsfeld is at the Pentagon.

3:55 p.m.: Giuliani now says the number of critically injured in New York City is up to 200 with 2,100 total
injuries reported.

4 p.m: CNN National Security Correspondent David Ensor reports that U.S. officials say there are "good indications"
that Saudi militant Osama bin Laden, suspected of coordinating the bombings of two U.S. embassies in 1998, is
involved in the attacks, based on "new and specific" information developed since the attacks.

4:10 p.m.: Building 7 of the World Trade Center complex is reported on fire.

4:20 p.m.: U.S. Sen. Bob Graham, D-Florida, chairman of the Senate Intelligence Committee, says he was "not
surprised there was an attack (but) was surprised at the specificity." He says he was "shocked at what actually
happened -- the extent of it."

4:25 p.m.: The American Stock Exchange, the Nasdaq and the New York Stock Exchange say they will remain closed
Wednesday.

4:30 p.m.: The president leaves Offutt Air Force Base in Nebraska aboard Air Force One to return to Washington.

5:15 p.m.: CNN Military Affairs Correspondent Jamie McIntyre reports fires are still burning in part of the
Pentagon. No death figures have been released yet.

5:20 p.m.: The 47-story Building 7 of the World Trade Center complex collapses. The evacuated building is damaged
when the twin towers across the street collapse earlier in the day. Other nearby buildings in the area remain
ablaze.

5:30 p.m.: CNN Senior White House Correspondent John King reports that U.S. officials say the plane that crashed in
Pennsylvania could have been headed for one of three possible targets: Camp David, the White House or the U.S.
Capitol building.

6 p.m.: Explosions are heard in Kabul, Afghanistan, hours after terrorist attacks targeted financial and military
centers in the United States. The attacks occurred at 2:30 a.m. local time. Afghanistan is believed to be where bin
Laden, who U.S. officials say is possibly behind Tuesday's deadly attacks, is located. U.S. officials say later that
the United States had no involvement in the incident whatsoever. The attack is credited to the Northern Alliance, a
group fighting the Taliban in the country's ongoing civil war.

6:10 p.m.:Giuliani urges New Yorkers to stay home Wednesday if they can.

6:40 p.m.: Rumsfeld, the U.S. defense secretary, holds a news conference in the Pentagon, noting the building is
operational. "It will be in business tomorrow," he says.

6:54 p.m.: Bush arrives back at the White House aboard Marine One and is scheduled to address the nation at 8:30
p.m. The president earlier landed at Andrews Air Force Base in Maryland with a three-fighter jet escort. CNN's John
King reports Laura Bush arrived earlier by motorcade from a "secure location."

7:17 p.m.: U.S. Attorney General John Ashcroft says the FBI is setting up a Web site for tips on the attacks:
www.ifccfbi.gov. He also says family and friends of possible victims can leave contact information at 800-331-0075.

7:02 p.m.: CNN's Paula Zahn reports the Marriott Hotel near the World Trade Center is on the verge of collapse and
says some New York bridges are now open to outbound traffic.

7:45 p.m.: The New York Police Department says that at least 78 officers are missing. The city also says that as
many as half of the first 400 firefighters on the scene were killed.

8:30 p.m.: President Bush addresses the nation, saying "thousands of lives were suddenly ended by evil" and asks
for prayers for the families and friends of Tuesday's victims. "These acts shattered steel, but they cannot dent the
steel of American resolve," he says. The president says the U.S. government will make no distinction between the
terrorists who committed the acts and those who harbor them. He adds that government offices in Washington are
reopening for essential personnel Tuesday night and for all workers Wednesday.

9:22 p.m.: CNN's McIntyre reports the fire at the Pentagon is still burning and is considered contained but not
under control.

9:57 p.m.: Giuliani says New York City schools will be closed Wednesday and no more volunteers are needed for
Tuesday evening's rescue efforts. He says there is hope that there are still people alive in rubble. He also says
that power is out on the westside of Manhattan and that health department tests show there are no airborne chemical
agents about which to worry.

10:49 p.m.: CNN Congressional Correspondent Jonathan Karl reports that Attorney General Ashcroft told members of
Congress that there were three to five hijackers on each plane armed only with knives.

10:56 p.m: CNN's Zahn reports that New York City police believe there are people alive in buildings near the World
Trade Center.

11:54 p.m.: CNN Washington Bureau Chief Frank Sesno reports that a government official told him there was an open
microphone on one of the hijacked planes and that sounds of discussion and "duress" were heard. Sesno also reports a
source says law enforcement has "credible" information and leads and is confident about the investigation.